As I write this post, I'm watching the October 14 Mac Keynote. You can watch it here. The first section, the State of the Mac, of the keynote is about why Mac is growing at such rapid pace (in the market). The presenter, in this section, talked the four or five essential qualities of a Mac that make it amazing. As I watched it, I thought, "I already know all this." Probably, most everyone watching the keynote knew all of the presenter's points. But that didn't matter. The presenter evangelized the same story, because that's the story that success for Apple. They never tire of talking about what makes them different, unique, remarkable, and worth switching to.
What makes you unique? Don't stop talking about it.
PS Steve Jobs is actually doing a better job sharing. Each time I see a keynote, Jobs speaks less and other Apple leaders speak more. Maybe Jobs is "getting it" too.